高寒草甸生态系统磷素循环  

The phosphorus cycling in an Alpine Meadow Ecosystem

作　　者：曹广民[1] 张金霞[1] 鲍新奎 周党卫[1] 

机构地区：[1]中国科学院海北高寒草甸生态系统定位站,西宁810001

出　　处：《生态学报》1999年第4期514-518,共5页Acta Ecologica Sinica

基　　金：国家"八五"攀登计划;海北高寒草甸生态系统定位站基金

摘　　要：试验在中国科学院海北高寒草甸生态系统定位站进行，实验样地设置在冬春草场上。应用分室模型，将高寒草甸生态系统分为大气、土壤、植物、食草动物 ４ 个分室，主要讨论了磷素在各分室内的贮量、流动方向、流通数量及其系统磷素的供需状况。高寒草甸生态系统磷素的循环过程是：大气分室通过降水输入土壤库磷量为０３６ｋｇ／ｈｍ ２·ａ；植物从土壤库摄取速效磷 ７０６ｋｇ／ｈｍ ２·ａ，这些磷素一部分（０５７ｋｇ／ｈｍ ２·ａ）以动物产品如骨、肉、奶、皮、毛等的形式永久迁出生态系统，另一部分（１３７ｋｇ／ｈｍ ２·ａ）成为植物有机态，其余部分通过土壤微生物分解归还于土壤。经过一个生长季，土壤净损耗磷素 １５８ｋｇ／ｈｍ ２，土壤速效磷素的缺乏，已经成为限制草场生产力提高和引起草场退化的重要营养限制因子之一。This study was carried out at Haibei Research Station of Alpine Meadow Ecoystem and the experiment plot was set on winter spring pasture.Using a compartment model.we divided the ecosystem into four compartments,they are atmosphere,soil,vegetation and grazing animal compartments.We measured the P storage in each of the compartments,and studied the direction and the amounts of P flowing among these compartments,and its' supply requirement state in the ecosystem.the P cycling process in the Alpine Meadow Ecosystem is the following:the atmosphere compartment transfers P 0.36kg/hm 2·a with precipitation to the soil pool.Vegetation compartment uptakes available P 7 06kg/hm 2·a from the soil pool.One part of it(0 57 kg/hm 2·a)was taken from the ecosystem in the form of animal products and the an other part(1 37kg/hm 2·a)becomes vegetation organism,and the rest returns to the soil pool through decomposition.During a growth season,the soil compartment loses net P 1 58kg/hm 2.For lack of available P in the soil pool,the P has become an important limiting factor which restricts the primary production in creasing and cause the pasture degradation.

关 键 词：高寒草甸 生态系统 磷素循环 

分 类 号：Q948.158[生物学—植物学]